Compact optical components, devices, and systems may be monolithically fabricated on various substrates to form integrated optical components, devices, and systems. Such fabrication may be achieved using various fabrication processes to process wafers, including micro fabrication processes used for fabricating integrated circuits (ICs), micro-electro-mechanical systems (MEMS), and other microstructures. The integrated optical components, devices, and systems may be monolithically integrated with ICs, MEMS, and other microstructures on the same chip to provide various useful functions. Fabrication of such integrated devices with optical components or devices generally includes wafer-level fabrication processes and packaging after dice on a single wafer are separated into chips by, e.g., dicing or sawing. The individually packaged chips are then tested.
In fabrication of integrated electronic circuits, a portion of the IC testing can be performed at the wafer level prior to separation of the dice. This wafer level testing measures the performance or identifies defective components and dice. Hence based on such testing at the wafer level, defective dice may be removed from subsequent processes including the packaging and testing of individual chips. Labor and costs associated with subsequent processes for the defective dice, therefore, can be significantly reduced. Various wafer-level testing systems have been developed for testing ICs at the wafer level.